Adriatic Sea, Italian Mare Adriatico, Bosnian, Croatian, and Montenegrin Jadransko More, Albanian Deti i Adriatikut, arm of the Mediterranean Sea, lying between the Italian and Balkan peninsulas. The Strait of Otranto at its southeasterly limit links it with the Ionian Sea. It is about 500 miles (800 km) long with an average width of 100 miles, a maximum depth of 4,035 feet (1,324 metres), and an area of 50,590 sq mi (131,050 sq km). The Adriatic has been of great importance in the historical development of Mediterranean Europe and is of considerable scientific interest in itself. Modern study of the Adriatic has been carried out mainly under the auspices of several Italian and Balkan scientific institutes.

Warm weather and a rich history have made the Adriatic Coast a popular destination despite the …

Encyclopædia Britannica, Inc.

There is a striking contrast between its two shores. The Italian coast is relatively straight and continuous, having no islands, whereas the Croatian coast is full of both large and small islands, generally oblong in shape and running parallel to the continental shore. Many tortuous straits form inlets between the islands similar to those of the Norwegian fjords and make the coastline very intricate.

The walled old city of Dubrovnik, Croatia, on the Adriatic Sea.

Dennis Jarvis (CC-BY-2.0) (A Britannica Publishing Partner)

The depths of the Adriatic near its shores bear a close relationship to the physiography of the adjacent coasts. Wherever such coasts are high and mountainous, the nearby sea depths are considerable, as in the case of the Istrian and Dalmatian areas of Slovenia and Croatia. Where low and sandy shores are found, the nearby sea is shallow, as in the vicinity of Venice or, farther south, near the delta of the Italian Po River. Generally speaking, the waters are shallow all along the Italian coast. The site of maximum depth of the Adriatic Sea is situated south of the central area; average depth is 1,457 feet (444 metres).

The Adriatic has two types of rather special sea bottoms, difficult to arrange in a rigorous classification but very common in the Mediterranean, namely, inlet-derived sediments and heat-altered sediments of the sea bottom proper. In general, the seabed consists of a yellowish mud and sand, containing fragments of shells, fossil mollusks, and corals. The main winds prevailing in the area are the bora, a strong northeast wind that blows from the nearby mountains into the sea, and a southeasterly wind named the sirocco that is less troublesome from a navigational point of view. During the six winter months, bora and sirocco alternate, with or without an interval of a few days calm. The tides of the Adriatic, which have been intensively studied, follow a complicated pattern, sweeping into the region from the south and being linked with those of the Ionian Sea.

The tidal range is about three feet, in contrast to the general Mediterranean tidal range of about 0.9 foot. The surface currents are chiefly influenced by the blowing winds, with currents spurred by north winds reaching a speed of four miles per hour.

Temperatures in the surface layers of the sea reach 75–77 °F (24–25 °C) during the month of August, and the minimum readings, some 50 °F (10 °C), are usually reached during January and February. In the northern Adriatic, river mouth temperatures are even lower because the waters are cooled by melting ice and snow. At greater depths (820–980 feet) the maximum temperatures fluctuate around 57 °F (14 °C), while minimum temperatures are about 52 °F (11 °C).

The Adriatic Sea, like the Mediterranean in general, is deficient in life; nutrient content, as indicated by the amount of phosphates and nitrates, is extremely low. Three main areas of marine life may nevertheless be recognized. In the northern Adriatic area, significant winter cooling and a lowered salinity further impoverish the typical Mediterranean marine life. In the middle Adriatic area, life is much richer than farther north, while the southern Adriatic area has its own distinctive forms of life.

Learn More in these related articles:

...Baltic, Adriatic, and Black seas. The Baltic has gone from being naturally nutrient-poor and diverse in species to being nutrient-rich and degraded in its ecosystems within a few decades. In the Adriatic Sea, rising nutrient levels have generated a large increase in phytoplankton. Nutrients in the runoff flowing into the Black Sea seem to be contributing factors in the invasion and...

...Sea north of Crete and bounded on the west and north by the coast of Greece and on the east by the coast of Turkey. The Aegean Sea contains the numerous islands of the Grecian archipelago. The Adriatic Sea, northwest of the main body of the eastern Mediterranean Sea, is bounded by Italy to the west and north and by Slovenia, Croatia, Bosnia and Herzegovina, Montenegro, and Albania to the...

easternmost of Europe’s three great southern peninsulas. There is not universal agreement on the region’s components. The Balkans are usually characterized as comprising Albania, Bosnia and Herzegovina, Bulgaria, Croatia, Kosovo, Macedonia, Montenegro, Romania, Serbia, and Slovenia...

Italy is separated from Eastern Europe by a baylike arm of the Mediterranean Sea-the Adriatic Sea. It was named for Adria, which was a flourishing port during Roman times. About 500 miles (800 kilometers) long, the Adriatic Sea has an average width of about 100 miles (160 kilometers). Its maximum depth is 4,100 feet (1,250 meters).